ATLANTIC CITY — A 28-year-old city man was arrested Monday night after staff at the police Surveillance Center found footage of him allegedly firing a handgun. According to police, officers responded to an alert from the city’s gunshot-detection system in the 200 block of Dr. Martin Luther King Jr. Boulevard. Police said officers did not initially find any witnesses or evidence of gunfire. Police said Surveillance Center personnel then reviewed camera footage from the area and found a man firing a gun. Less than an hour later, police said, a man matching the shooter’s description returned to the area. Surveillance Center staff alerted patrol officers, and Officer La’Tray Butcher located Jamar Cherry. Police said Cherry threw a handgun to the ground as Butcher approached him, and he was taken into custody. Cherry was charged with unlawful possession of a weapon and certain persons not to possess a weapon, and was sent to the Atlantic County Jail.